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A181662 a(n) = the smallest positive integral multiple of 2^n not in the range of the Euler phi function, or -1 if no such multiple exists. 0

%I

%S 3,14,68,152,304,608,1984,3968,12032,24064,48128,96256,192512,385024,

%T 770048,1540096,3080192,6160384,12320768,24641536,49283072,98566144,

%U 197132288,394264576,788529152,1577058304,3154116608,6308233216,12616466432,25232932864,50465865728,100931731456

%N a(n) = the smallest positive integral multiple of 2^n not in the range of the Euler phi function, or -1 if no such multiple exists.

%D David Harden, Posting to Sequence Fans Mailing List, Sep 19 2010

%F a(n) = A058887(n)*2^n

%Y Cf. A005277, A007617, A058887.

%K nonn

%O 0,1

%A _N. J. A. Sloane_, Nov 18 2010

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Last modified September 21 15:47 EDT 2021. Contains 347598 sequences. (Running on oeis4.)